1. Field of the Invention
The present invention relates to a laser microscope.
This application is based on Japanese Patent Application No. 2007-113042, the content of which is incorporated herein by reference.
2. Description of Related Art
A multiphoton excitation laser microscope has been known in which ultrashort pulse laser light outputted from an ultrashort pulse laser light source propagates through a first optical fiber, is introduced into a negative dispersion medium so that the laser light that has propagated through the first optical fiber is negatively chirped, propagates through a second optical fiber, and is introduced into a microscope body (see S. W. Clark et al., “Fiber delivery of femtosecond pulses from a Ti:sapphire laser.”, Opt. Lett. 26, 1320 (2001), pp. 1320-1322, for example).
According to such a laser microscope, since the optical system between the output port of the second optical fiber and the microscope is relatively simple, high-power ultrashort pulse laser light can be efficiently delivered.
However, in the laser microscope described in the description of S. W. Clark et al., changing in wavelength of the ultrashort pulse laser light or replacing the objective lens in the microscope body disrupts the balance between the nonlinear effect in the first optical fiber and the nonlinear effect in the second optical fiber or changes the total amount of positive dispersion in the region from the output port of the second optical fiber to the specimen. Therefore, the objective lens in the microscope body cannot output ultrashort pulse laser light having a desired pulse width, and hence a multiphoton excitation phenomenon cannot be generated efficiently in the specimen.